Getting selected text in an iframe plugin

Hello.

I have a iframe plugin that generates a link from a cms content list. I want to add the link around the selected text when the ok button is clicked. It all works, except i can't get the selected text.

I have tried using the answer supplied here:

http://stackoverflow.com/questions/2385609/getting-selected-text-win-ckeditor-plugin

so like this:

var okListener = function(ev) {
      console.log(CKEDITOR);
      var mySelection = CKEDITOR.editor.getSelection();
      if (CKEDITOR.env.ie) {
          mySelection.unlock(true);
          selectedText = mySelection.getNative().createRange().text;
      } else {
          selectedText = mySelection.getNative();
      }      
      console.log(selectedText);